The present invention relates to a device for holding an electronic card in a corresponding reading device.
Within the automotive field, it is known to replace a conventional key cooperating with a mechanical lock by a card containing an electronic device. To access a vehicle, the card transmits a signal to a receiver situated in the cabin of the vehicle. If the receiver recognizes the card, access to board the vehicle is permitted. The information received by the receiver is for example provided to a device making it possible to open and close the doors. The card can also serve as ignition key and a reader is in this case located in the cabin of the vehicle.
The card is generally of rectangular shape and is made of a synthetic material. It carries an electronic circuit, electrical contacts and, generally, a transmitter, possibly receiver, for exchanging data remotely. The electrical contacts are optional since the exchange of information between the card and the reading device can be effected for example by inductive, radiofrequency or infrared coupling.
The reader generally takes the form of a casing furnished on its front face with a slot into which the card is inserted. The insertion of the card into the casing is done manually. It is then necessary to make provision for good positioning and good holding of the card in the reader so as to guarantee a good exchange of information.
In a motor vehicle, the use of a card to provide for functions such as starting requires particular precautions. The reading device into which the card is introduced must provide, among other things, for accurate positioning and light gripping of the card during the placing of the card into the reading device. It is moreover necessary to prevent the card from vibrating in its housing so as to avoid any risk of wear and of sound nuisance. Finally, latching and retention under considerable force must also be envisaged if one wishes the card to remain in the reading device when the motor vehicle is used.
Devices for latching an electronic card in a reader already exist. Most of these systems relate to the field of banking and more generally to card-based payment devices. Within this field, there is no vibration stress as in a motor vehicle.
Document U.S. Pat. No. 4,807,059 discloses a device adapted for receiving and holding a memory card or diskette. This device provides for holding and immobilizing the diskette during the reading and/or the transferring of data to an associated computer. However, such a device is intended neither to be put in place in a vehicle nor to undergo considerable and frequent vibrations. The means of holding the card are not adapted, in particular, for damping these vibrations.
Document U.S. Pat. No. 3,851,505 relates to a device for immobilizing a parking card in a vehicle. This parking card is not in electronic contact with the vehicle. The immobilizing device comprises in particular an immobilizing peg which inserts into an opening made on the card so as to immobilize it positionally. The insertion of the peg is operated by an electromagnet. Here, one is dealing only with an immobilizing device and no means exist for damping the vibrations transmitted by the vehicle.
Document U.S. Pat. No. 6,129,572 relates to an electrical connector furnished with a latch for retaining a printed circuit card. The card is furnished with a connection device (pins) which fits into a complementary part made on the connector. An immobilizing latch holds the card immobilized longitudinally while it is not unlatched. However, this card is not intended to be put in place in a vehicle and such a device does not make it possible to avoid the transmission of the vibrations of the vehicle to the card during the movement of the vehicle.
In the automotive field, latching devices exist. Thus, document EP-0 964 357-A describes for example a casing intended to receive a rigid or semi-rigid data medium in which the data medium comprises a lateral immobilizing catch. For its part, the casing receiving this medium comprises a controlled lever for immobilizing the medium which is mounted pivotably so as to be able, in an immobilizing position, to be positioned inside the immobilizing catch so as to preclude any withdrawal of the medium from the reading device.
This device, just like the other known devices of the prior art, certainly makes it possible to latch the card in the reader, thus preventing any inadvertent withdrawal of the card from the reader during use of the vehicle, but does not provide for good holding in space of the card. Moreover, the latching of the card in its housing may, in certain cases, be related to relatively considerable mechanical stresses exerted on the card. Internal tensions then appear inside the reader.
The aim of the present invention is thus to provide a device for holding an electronic card in a corresponding reader making it possible to provide excellent holding of the card in the reader. Preferably, this device will make it possible to avoid the appearance of considerable stresses inside the reader.
For this purpose, the device that it proposes is a device for holding an electronic card in a reading device for which the card is inserted manually into a housing of the reading device so as to arrive at a position, the so-called reading position, allowing the reading of the card by the reading device.
According to the invention, this holding device comprises elastic means acting on the card when the latter is in the reading position in three substantially perpendicular directions of action.
In this way, the card is held perfectly and the mechanical stresses which are exerted on it are perfectly controlled.
In one embodiment, a first spring is disposed at the back of the housing in the direction of insertion of the card, a second spring acts on a face of the card and a third spring acts on a lateral edge of the card, the card comprising an upper face, a lower face, a front edge inserted first into the housing, a rear edge opposite the front edge and two lateral edges connecting the front edge to the rear edge. Here the elastic means are springs but other elastic means, such as foam or rubber pads, may also be used. Likewise, the points of action of the elastic means are preferred points of action adapted to the most frequently encountered case of rectangular electronic cards.
In a variant embodiment, the card may exhibit a notch intended to cooperate with a boss of a spring in such a way as to determine a stopping position in the direction of insertion of the card into its housing.
In this variant, provision may be made for two bosses to be provided on the spring thus defining two stopping positions in the direction of insertion of the card into the housing.
To prevent untimely withdrawal of the card from the reading device, a device for latching the card in the housing is advantageously provided. The latching may then be carried out by holding a flexible arm in a recess provided in the card so as to receive it in the reading position. Another embodiment makes provision for example for the latching to be carried out by inserting a latch or the like into a recess provided for this purpose in the card. Finally, in another embodiment, the latching is for example carried out by inserting an index or similar into a recess provided for this purpose in the card, a latch being provided to hold the index in the recess.
When latching is provided for, the latter is preferably carried out with the aid of an electromagnet. Thus control may be effected electrically and a considerable latching force is obtained even for a small-sized latching device.
An advantageous embodiment makes provision for the elastic means to comprise a spring shaped in such a way as to exhibit a boss cooperating with a recess of the card in the reading position and extending toward the back of the housing in such a way that its free end is disposed between the back of the housing and a front edge of the card and exerts on the latter, in the reading position, a stress in the direction of insertion of the card into its housing. Thus, one and the same component plays the role of two springs, thus limiting the costs of the device and its bulk.
The present invention also relates to a device for reading an electronic card incorporating a holding device as described above.